---
title: event_data
framework: Kernel
role: symbol
role_heading: Instance Property
platforms: [macOS 10.9+]
path: kernel/kern_event_msg/1446985-event_data
---

# event_data

Any additional data about this event. Format will depend on the vendor_code, kev_class, kev_subclass, and event_code. The length of the event_data can be determined using total_size - KEV_MSG_HEADER_SIZE.

## Declaration

```occ
u_int32_t event_data[1];
```

## See Also

### Fields

- [total_size](kernel/kern_event_msg/1446925-total_size.md)
- [vendor_code](kernel/kern_event_msg/1446929-vendor_code.md)
- [kev_class](kernel/kern_event_msg/1446955-kev_class.md)
- [kev_subclass](kernel/kern_event_msg/1446935-kev_subclass.md)
- [id](kernel/kern_event_msg/1446959-id.md)
- [event_code](kernel/kern_event_msg/1446927-event_code.md)